The present invention relates to the non-surgical repositioning of craniofacial bones following disease or trauma, and in particular, to a process employing osseointegrated fixtures and a malleable bar fixed between the osseointegrated fixtures having at least one non-linear segment which is periodically straightened so as to apply a displacing force between the osseointegrated fixtures.
Craniofacial disease or trauma may often result in the loss of form and/or function to the craniofacial structure. Restoring form and/or function to the craniofacial structure often requires that the craniofacial bones be repositioned to move nearly approximate the natural location of the bones and to allow for the proper fitting of prostheses. Properly formed and fitted prostheses in conjunction with properly positioned craniofacial bones may lead to a succesful restoration of the patient's facial form and lost or impaired function.
The first step is to reposition the craniofacial bones. While surgery is the normal option, it is desirable to avoid, to the extent practicable, major surgical intervention to an area already subjected to severe trauma. Fortunately, bones are capable of migration under steady pressure over a period of time. In fact, the original loss of form or function in some patients may be a result of the migration of bones due to the loss of supporting structure following surgery or trauma.
It is known to use mechanical devices implanted in the bone structure of a patient in order to stabilize the bone structure following surgery. For example, U.S. Pat. No. 5,752,955 to Errico discloses a mechanical cross-link device for use in orthopedic surgery, particularly surgery of the spine, so as to provide increased stability of the spine.
Similarly, U.S. Pat. No. 5,725,582 to Bevan et al. discloses a surgical implant formed from a strand of biocompatible material for the purpose of spinal stabilization.
Furthermore, mechanical devices are known for the displacement of bone structures. U.S. Pat. No. 5,700,263 to Schendel discloses a bone distraction apparatus for osteosynthesis includes a first member housed telescopically within a second member. The two members are attached to bone segments. A ratchet wheel with teeth engages the first member and causes it to telescopically extend from the second member on an arcuate path.
U.S. Pat. No. 5,681,311 issued to Foley, et al. discloses a bone fixation apparatus with plates which slide relative to the other.
Hoffman et al. (U.S. Pat. No. 5,538,427) disclose a palatal wire used in conjunction with a bone anchor.
It is also known to use a periodically bent arch wire in orthodontia to urge teeth to a preferred position. An individual metal band is secured around each tooth. A bracket is then attached to each metal band. The arch wire is then attached to each bracket. In order to effect a realignment of specific teeth, the arch wire must be bent or twisted. The bends or twists in the arch wire are effected while the arch wire is removed from the brackets. After making the requisite bends, the arch wire is reinstalled into the brackets where the bends induce a corrective force on the particular teeth which require repositioning.
The prior art devices are generally mechanically complicated, have difficulty in producing controllable results, and often require major surgical intervention.
The limitations and disadvantages of the prior art are overcome by the present invention as described below.